Image courtesy of http://caribbean-ecoteam.fws.gov/green_cay_index.htm

Kingdom: Animalia
Phylum: Craniata
Class: Reptilia
Order: Squamata
Family: Teiidae
Genus: Amevia
Species: polops

Image courtesy of http://endangered.fws.gov/i/C1M.html

Map adapted from image found at

http://www.buystcroix.com/map.htm

Endagered Species Information 1996. http://fwie.fw.vt.edu/www/esis/lists/e154006.htm. Accessed on Feburary 17, 2003.

Green Cay National Wildlife Refuge. General Information. http://caribbean-ecoteam.fws.gov/green_cay_index.htm. Accessed on March 3, 2003.

U.S. Fish and Wildlife Service. Division of Endangered Species. http://endangered.fws.gov/i/c/sac1m.html. Accessed on Feburary 17, 2003.

United States Geological Survey. Status and Trends of the Nations Biological Resources; Caribbean Islands. http://biology.usgs.gov/s+t/SNT/noframe/cr133.htm Accessed on March 20, 2003.

An adult St. Croix Ground Lizard averages 50-65 mm in snout vent length.  It is characterized by a dorsal pattern of light brown and dark brown or black, white and dark brown logitudnal stripes, a light gray abdomen with lateral blue margins, pinkish undersides of legs, throat, and chest, and a tail pattern of alternating white and blue rings. (Endangered 1996, U.S. Fish and Wildlife) The pupil of the eye has a figure-eight shape, and the iris a light grayish-brown. There are approximatly 2500 individuals located on Green Cay and 50 individuals on Protestant Cay. (U.S. Fish and Wildlife) The St. Croix Ground Lizard inhabits leaf litter, tidal litter, other loose substrate, and crab burrows in beachland and upland forest. (U.S. Fish and Wildlife)  The individuals feed on small white moths, hermit crabs, sand flease, arthropods and crustaceans, orchestria, annelids and dermaterones (U.S. Fish and Wildlife).  Little is known about the St.Groix Ground Lizard regarding development, reproduction, or lifespan. 
 

The St. Croix Lizard was designated as endangered by the Endangered Federal Register, June 3, 1977 (Endangered, 1996).

The United States Federal Wildlife Service is responsible for the management, recovery, listing and law enforcement/protection of this species (US Fish and Wildlife).

The Fish and Wildlife Service and National Park Service signed a cooperative agreement in January 1982 for the National Park Service to provide protection of the species on Green Cay National Wildlife Refuge (US Fish and Wildlife).

 

The only known remaining natural populations of the St. Croix ground lizard (Ameiva Polops) are found within the US Virgin Islands off the northern shore of St. Croix Island on Green Cay and Protestant Cay (Endangered, 1996). These locations have both been designated as critical habitat for A. polops.

The introduction of the Small Indian Mongoose (Herpestes auropunctatus) in 1984 and human disturbance are both responsible for the elimination of A. polops from the mainland of St. Croix and continue threaten the species viability. The Indian Mongoose is known to be highly destructive to native reptile fauna when they become established on small Islands or Cays (USGS). The accidental introduction of the mongoose onto Green Cay or Protestant Cay would most likely result in the extinction of A. polops.

Indian Mongoose

Image courtesy of http://hbs.bishopmuseumhttp://hbs.bishopmuseum.org/good-bad/mongoose.html.org/good-bad/mongoose.html

The extensive development of coastal areas around St. Croix also contributed to the decline in the population of A. polops. “Beautification practices” like raking and undergrowth removal modify critical features of A. polops‘s habitat (Green Cay). These practices result in a decline in leaf and tidal litter, loose substrate, and crab burrows (Green Cay).

The population of A. polops is currently estimated to be between 360-2500 on Green Cay and 50 on protestant Cay (Endangered, 1996). Their small population sizes and reduced habitat area make A. polops particularly vulnerable to extinction as a result of genetic bottlenecking. If a natural disaster of considerable proportions were to occur then the entire species could be eliminated because there wouldn't be enough genetic variability within the population for natural selection to act on.

Some steps have been taken to help preserve the A. polops. The most significant of these was the establishment of the Green Cay National Wildlife Refuge in 1977 by the U.S. Fish and Wildlife service. This was done to protect the largest remaining population of A. polops (Endangered, 1996). The refuge provides protection for 14 of the 18 acres of designated critical habitat for A. polops on Green Cay and is closed to the public (Green Cay). However, if the species is going to persist then more conservation measures need to be taken.

The current conservation goal for A. polops as stated by National Park Service is to establish a stable population on Green Cay and Protestant Cay and to establish a minimum self sustaining population of 500 individuals on Buck Island Reef National Monument, where no lizards are known to reside currently (Endangered, 1996). This Island could serve as an experimental release sight for the lizards. In order for this project to succeed a massive eradication program must first be implemented to remove the Indian Mongoose from this area.

The Recovery Plan approved by the U.S. fish and Wild life service in 1984 included the following suggestions:

1) The eradication of the Indian Mongoose in and around St. Croix. This would allow the lizard to be successfully transferred and established in areas such as Buck Island, where populations of lizards once thrived.

2) A few lizards should be transplanted to Zoos where they can be actively bred for reintroduction later.

3) Human disturbance and housing and resort development should be restricted in the area of the lizard’s habitat.

4) The continued protection of the habitat and present population on Green Cay.

The implementation of these policies has potentially important economic consequences. The full protection of Green Cay and Protestant Cay would mean limiting potentially lucrative tourism in these areas. Protestant Cay is currently leased by a hotel complex. In addition, the eradication of the Indian Mongoose would require a considerable degree of money, time and labor.

The prospects for A. Polops do not look promising. Present and future threats to the species are numerous and the measures needed to insure their survival are costly. The future of the A. polops populations will depend largely on the fate of its remaining habitat. An
increase in human disturbance or habitat alteration resulting from recreational activities, would be
detrimental. Given that A. polops is a species of no commercial value and of little aesthetic value when it comes to tourism, the incentive for taking the neccesary steps to save this species do not appear strong at this time.

Authors: Robin Forbes-Lorman, Josie Caton, Sarah Biber
Creation/revision date: 4 April 2003